Frequency Domain Identification Experiment on a Large Flexible Structure

Recent experiences in the field of flexible structure control in space have indicated a need for on-orbit system identification to support robust control redesign to avoid in-flight instabilities and maintain high spacecraft performance. This paper highlights an automated frequency domain system identification methodology recently developed to fulfill this need. The methodology is focused to support 1) the estimation of system quantities useful for robust control analysis and design, 2) experiment design tailored to performing system identification in a typically constrained on-orbit environment 3) the automation of operations to reduce "human in the loop" requirements. A basic overview of the methodology is presented first, followed by an experimental verification of the approach performed on the JPL/AFAL test-bed facility.